From f4b477c47332367d35686bd2b808c2156b96d7c7 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Sat, 10 Jan 2009 11:12:09 +0000 Subject: [PATCH] rbtree: add const qualifier to some functions MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The 'rb_first()', 'rb_last()', 'rb_next()' and 'rb_prev()' calls take a pointer to an RB node or RB root. They do not change the pointed objects, so add a 'const' qualifier in order to make life of the users of these functions easier. Indeed, if I have my own constant pointer &const struct my_type *p, and I call 'rb_next(&p->rb)', I get a GCC warning: warning: passing argument 1 of ‘rb_next’ discards qualifiers from pointer target type Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse Signed-off-by: Linus Torvalds --- include/linux/rbtree.h | 8 ++++---- lib/rbtree.c | 12 ++++++------ 2 files changed, 10 insertions(+), 10 deletions(-) diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h index 344bc3495ddb..9c295411d01f 100644 --- a/include/linux/rbtree.h +++ b/include/linux/rbtree.h @@ -140,10 +140,10 @@ extern void rb_insert_color(struct rb_node *, struct rb_root *); extern void rb_erase(struct rb_node *, struct rb_root *); /* Find logical next and previous nodes in a tree */ -extern struct rb_node *rb_next(struct rb_node *); -extern struct rb_node *rb_prev(struct rb_node *); -extern struct rb_node *rb_first(struct rb_root *); -extern struct rb_node *rb_last(struct rb_root *); +extern struct rb_node *rb_next(const struct rb_node *); +extern struct rb_node *rb_prev(const struct rb_node *); +extern struct rb_node *rb_first(const struct rb_root *); +extern struct rb_node *rb_last(const struct rb_root *); /* Fast replacement of a single node without remove/rebalance/add/rebalance */ extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, diff --git a/lib/rbtree.c b/lib/rbtree.c index 48499c2d88cc..9956b99649f0 100644 --- a/lib/rbtree.c +++ b/lib/rbtree.c @@ -292,7 +292,7 @@ EXPORT_SYMBOL(rb_erase); /* * This function returns the first node (in sort order) of the tree. */ -struct rb_node *rb_first(struct rb_root *root) +struct rb_node *rb_first(const struct rb_root *root) { struct rb_node *n; @@ -305,7 +305,7 @@ struct rb_node *rb_first(struct rb_root *root) } EXPORT_SYMBOL(rb_first); -struct rb_node *rb_last(struct rb_root *root) +struct rb_node *rb_last(const struct rb_root *root) { struct rb_node *n; @@ -318,7 +318,7 @@ struct rb_node *rb_last(struct rb_root *root) } EXPORT_SYMBOL(rb_last); -struct rb_node *rb_next(struct rb_node *node) +struct rb_node *rb_next(const struct rb_node *node) { struct rb_node *parent; @@ -331,7 +331,7 @@ struct rb_node *rb_next(struct rb_node *node) node = node->rb_right; while (node->rb_left) node=node->rb_left; - return node; + return (struct rb_node *)node; } /* No right-hand children. Everything down and left is @@ -347,7 +347,7 @@ struct rb_node *rb_next(struct rb_node *node) } EXPORT_SYMBOL(rb_next); -struct rb_node *rb_prev(struct rb_node *node) +struct rb_node *rb_prev(const struct rb_node *node) { struct rb_node *parent; @@ -360,7 +360,7 @@ struct rb_node *rb_prev(struct rb_node *node) node = node->rb_left; while (node->rb_right) node=node->rb_right; - return node; + return (struct rb_node *)node; } /* No left-hand children. Go up till we find an ancestor which -- 2.20.1